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Highlights from Appendix B in <<The Craft of Scientific Writing>> by Michael Alley
1. The Period 句号
The period is the most powerful piece of punctuation. In effect, the period is a stop sign.
Avoid using periods to abbreviate.
2. The Comma 逗号
Whereas periods are stop signs in sentences, commas serve as yield signs.
1) The purpose of commas is to eliminate ambiguities.
2) Develop a consistency in your use of commas.
a) Insert a comma after an introductory phrase or clause. Ex: When feeding, a shark often mistakes undesirable food items for something it really desires.
b) Place commas around a parenthetical clause. Ex: The new conductor, which will be available next week, contains barium and copper.
c) Set off contrasting elements with commas. These expressions often begin with “but” or “not.” Ex: Many injuries result from shark bumps, not shark bites.
d) Separate items in a series of three items or more.
How many commas you insert depends on two factors: (1) whether an ambiguity would exist without a comma, and (2) where the document is published.
Ex: …nitrogen, oxygen, and hydrogen and carbon.
Ex: …neopentane, perdeuteroneopentane, or neooctane.
3. The Colon 冒号
The Colon. The colon is a valuable piece of punctuation in engineering and science.
1) One important use of colons is to introduce a formal list.
What is on the left side of a colon should stand alone as a sentence.
Example: We studied five types of Marsupialia: opossums, bandicoots, koalas, wombats, and kangaroos.
2) Besides introducing lists, colons are also used for definitions.
Example: The laboratory growth of this germanium crystal made possible a new astronomical tool: a gamma-ray detector with high-energy resolution.
3) Yet another use for colons is to introduce equations.
Example: … is calculated by the following relation:
4. The Semicolon (stronger than comma) 分号
Its purpose is to join elements of a sentence that are parallel in structure.
1) The best use of a semicolon is to connect complex items in a list.
Example: Four sites were considered for the research facility: Livermore, California; Albuquerque, New Mexico; Los Alamos, New Mexico; and Amarillo, Texas.
2) Another accepted use of the semicolon is to join two independent clauses closely linked in thought.
Example: No cure exists for Alzheimer’s disease; it brings dementia and slow death to thousands of Americans every year.
5. The Dash (em-dash, stronger than comma) 破折号
The dash is flexible, often acts as a parenthesis.
1) Dashes can set off parenthetical remarks that commas cannot clearly separate.
Example: The unique feature of the design is a continuous manifold, which follows a unidirectional—as opposed to serpentine—flow for the working fluid.
2) Dashes can also set off end phrases and clauses that would be difficult to read if separated by commas.
Example: After one year, we measured mirror reflectivity at 96%—a high percentage, but not as high as originally expected.
Note that em-dashes (—) are different from hyphens (-) and en-dashes (−). In scientific writing, the main use of an en-dash is to show a range: “Temperatures in Death Valley have varied from 15–134°F.”
6. Quotation Marks 引号
In the US, end quotation marks go outside of periods and commas, while in Europe and other parts of the world, quotation marks generally appear inside of periods and commas.
7. Hyphens 连字符
The trend in spelling compound nouns is away from the use of hyphens because hyphens make the writing appear more
complex. Therefore, you should write compound nouns as
- cross section
- flow field
- fly ash
However, when compounds appear as adjectives in front of nouns, the trend is to use a hyphen to avoid misleading the reader. Therefore, write
- cross-sectional measurements
- flow-field predictions
- fly-ash modeling
8. The Slash 斜线
To reduce complexity, avoid word constructions that incorporate slashes.
In other words, do not write
- …he/she…
- …s/he…
- …experimental/computational techniques…
Instead, write
- …he or she… (or revise the sentence to use they)
- …she or he… (or revise the sentence to use they)
- …experimental and computational techniques…